FIELD OF THE INVENTION
This invention relates generally to the field of multimedia information systems and, more particularly, to interactive multimedia systems that provide storage and retrieval of digital information.
Multimedia systems are generally understood to be microprocessor-based systems which can store and display more than one from of information. In this context, information can take the form of video information, textual information, photographic information, graphic information including animation and visualization, or audio information. Multimedia systems are finding increasing use in a variety of applications, such as point of sale terminals in retail stores and directories in public buildings, and for education and training in a variety of settings.
Multimedia systems almost always include some interactive capability which allows a user to select and control the output of the different types of information. As used in the following description, the term "interactive" refers to processes by which user inputs cause a system to follow pre-established logical procedures.
Virtually all modern computers can display both text and graphics, and many can produce sound. These computers, however, are not generally considered to be multimedia systems, as that term is generally understood to include systems having a greater capability of displaying both sound and visual information, including motion video, than do conventional computers.
One type of existing multimedia system uses videodisks to store video and audio information. Such systems usually also include a standard computer keyboard as well as other input devices, such as a mouse, a joystick, or a touch sensitive display screen. There are even videodisk systems that use voice recognition units as input devices.
The processors controlling the interactive functions of such videodisk-based multimedia systems generally rely upon standard computer operating systems, such as MS-DOS from Microsoft Corporation, the Macintosh operating system from Apple Computer, Inc., or some version of a Unix operating system. This is where the standardization ends, however. To create, manipulate and output a specific body of information (sometimes called a "document") in a multimedia system of this type, the processors must use special run-time modules and which are frequently, but not always, specific to each document.
Videodisk-based systems also have disadvantages which limit their use. Many of these disadvantages arise from the analog nature of the video information stored on the disk. For example, because videodisk-based systems must usually handle digital as well as analog data, such systems require two separate storage devices and two separate display terminals. Furthermore, analog information of the type which can be stored on a videodisk cannot be transmitted over telephone lines or other transmission media which can transmit digital data.
There currently exist multimedia systems which use only digital information and thus avoid some of the disadvantages of videodisk-based systems. Such systems had been too expensive for mass commercial use, but Intel Corporation recently released a relatively low cost chip set incorporating a technology which has been given the name "Digital Video Interactive" (DVI). Add-on boards for microprocessors based on the DVI technology have been marketed under the trademarks ACTIONMEDIA 750 and ACTIONMEDIA II, and the chips presently available are designated the 82750PB and the 82750DB. The DVI technology has made an all-digital multimedia system economically practical for a wide range of consumers.
Even these all-digital systems have their limitations, however. Currently there are no standard conventions for storing or accessing multimedia information or for using or creating multimedia documents. There are not even standard conventions for assigning file names or for operating input devices. Thus, a user must learn a new set of conventions whenever he changes systems and/or documents.
It is therefore an object of this invention to provide a standard set of conventions and formats for multimedia information systems and documents.
It is further an object of this invention to provide an interactive, all-digital multimedia system having predetermined conventions and standards for documents.
Yet another object of this invention is to provide a set of standard conventions for multimedia systems which makes it relatively easy for a user to create, select and manipulate the digital information in the various documents used in the system.
Still another object of this invention is to provide a common document structure which can be used for many different types of multimedia information.